Drum polishing apparatus

ABSTRACT

Drum tumbling apparatus for surface treatment of small metal objects which includes at least one drum, whose body is provided with hinged cover which can be opened in order to receive the objects and a treatment medium and thereafter closed. The drum is provided at each of its ends with integral wheel-like ends by which they lie on top of two parallel support rollers arranged in a rack one of the supports may be driven while the other runs freely. The apparatus includes a transport arrangement by which the drum can be removed for service for filling and emptying.

[ June 18, 1974 1,097,852 1/1961 Germany 1 DRUM POLISHING APPARATUS [76] Inventor:

Manfrid Dreher, l-lauptstr. 74, Engelsbrancl, Germany Feb. 9, 1973 Primary Examiner-Harold D. Whitehead Attorney, Agent, or Firm-Murray Schaffer [22] Filed:

Appl. No.: 331,042

ABSTRACT [30] Foreign Application Priority Data Drum tumbling apparatus for surface treatment of small metal objects which includes at least one drum, whose body is provided with hinged cover which can be opened in order to receive the objects and a treatment medium and thereafter closed. The drum is provided at each of its ends with integral wheel-like ends by which they lie on top of two parallel support rollers arranged in a rack one of the supports may be driven while the other runs freely. The apparatus includes a transport arrangement by which the drum can be removed for service for filling and emptying.

00 92L.4 mm 5 91 n O 537 2 2 5 2 b/ UB U S m M MWL T m m .D W a "9 m 4 "8 T 6 5 d 9 A n 1 4 D. H 3 n 1 CS y 5 m m fi m u." C m m mm 0 m .m h eD R M E 2 U T w Ne M 1 1.12m U C b .m R U.mF 1:11 1. 2 8 6 555 5 12.1.1 .1

2,209,080 7/1940 Gurtelmeier............... 51/164 FOREIGN PATENTS OR APPLICATIONS 256.588

2/1913 Germany 51/164 7 Claims, 11 Drawing Figures DRUM POLISHING APPARATUS BACKGROUND OF THE INVENTION The present invention relates to drum tumbling equipment.

Generally, tumbling apparatus of the type herein disclosed comprises a drum, which is adapted to be placed on to a cradle which includesroller means for revolving the drum by engaging its peripheral surface/The drum has a pivotal cover lid extending longitudinally between the ends which is openable so that the drum may be filled with the material to be polished, such as small nails, nuts, bolts, etc. together with an abrasive cleaner such as sand, corn husks, grit, etc. at a place remote from the cradle and then transported and lifted on to the cradle for rotation. After an interval of rotation, the drum is removed for emptying and then servicing.

In drum apparatus of this kind the servicing and emptying of the drum had to be done manually. For this, a number of manipulations were necessary, which had to be thoroughly supervised, expecially when the drum was being closed, in order to assurethat the drum does not open during the transport of the drum movement.

The object of the present invention is to improve this kind of drum apparatus in such a way that the closing lid of the drum is automatically opened and closed, so that the worker does not have to do this manually, and, further, to make it possible to service or empty the drum automatically.

SUMMARY OF THE INVENTION According to the present invention, two sided closure devices are arranged one at each end of the drum body so these closure devices act together with a stop memmber which is arranged at the back of the service station to activate an actuator for opening the lid and later on for closing the lid.

It is advantageous to construct this apparatus so that when the drum is to be opened, the closure lid pivots on its own, under the effect of gravity and when it is to be closed, it need only be rotated whereby the lid will also close by gravity. For this purpose, a control mechanism is provided by which the drum which has been transported to the servicing device for opening can be maneuvered into a position, in which the closure lid is arranged on the under side of the drum and by which the drum may be revolved to present the open lid on top for the filling position, and after the filling in such a position can be revolved again so that the closure lid closes itself, after which the activating devices causing polishing revolution of the drum may be placed. Preferably the control mechanism comprises suitable electrical circuiting.

The closing devices can be formed in different ways. One closing device which provides an especially dependable secure closing of the lid can be obtained with a pivotable latch mounted on the drum body, which in its closing position grips a pin which extends sideways from the lid, and which has a latching lever arranged therewith which works together with the stop member which in their locking position hold the locking levers in their locking position.

Such a maneuverable closing mechanism can also be used for drum apparatus with different design.

In order to make such apparatus: fully automatic, the service station is provided with a hoist for elevating the filling the drum and/or the treatment medium into the drum and for conveying the drum to and from the work or rotating stations. For fully automatic servicing of the opened drum an electricalcontrol system may be provided. Thereby, the latter is advantageously layed out in such a way that the hoist can be activated only when the drum to be serviced in the servicing station has first been safely opened and emptied andhas been put in its filling position.

DESCRIPTION OF THE DRAWINGS In the drawing an embodiment of the invention is shown:

FIG. 1 shows aperspective view of a drum apparatus in which the drum of the last work section has been transported with the help of the transporting device in the servicing device for filling, and/or emptying;

FIG. 2 shows a partial front view of the drum apparatus showing a drum in the servicingdevice, partly broken away;

FIG. 3 shows a cross section of a drum along the line 3-3 of FIG. 2, in larger dimension than FIG. 2,

whereby the drum is closed and is shortly before the position, in which the closing lid is being opened;

FIG. 4 shows a view similar to FIG. 3 in which the closure lid is being shown in its open position;

FIG. 5 shows a section indicated in FIG. 3 by a dashdotted circle in larger dimension than FIG. 3 for the view of a closing device which serves for closing the drum in closed condition;

FIG. 6 shows a view similar to FIG. 3 whereby the closing device is shown in open condition;

FIG. 7 shows a view similar to FIG. 3 whereby the drum is shown in its filling position;

FIG. 8 is a view similar to FIG. 7 after the closing lid of the drum has moved itself in its closing position;

FIG. 9 is a view similar to FIG. 8 whereby the locking levers of the closing device with the help of an activating device have been brought in a locking position; and

FIG. 10 shows a side view of the activating device for activating the locking lever of the closing device in the DESCRIPTION OF THE INVENTION As seen in FIG. 1 the apparatus comprises a plurality of units in assembly for revolving the tumbling drums, generally depicted by the numeral 10. Located adjacent the drum revolving assembly is a service station, generally depicted by the numeral 20 which is provided with a feed tower 22 generally well known located at the rear side. The feed tower is adapted to feed a drum 29 with the help of an overhead conveyor 24 to the servicing table 26 where the drum may be filled with or emptied of the workpieces to be treated in the drum or otherwised tumbled, as well as with the treating medium such as the abrasive material and liquid carrier necessary. In the table 26, a sieve-like top 28 is provided so that when the drum is emptied, the medium may be separated from the workpieces. The workpieces and medium may be fed to the service station through the feed tower.

The tumbling assembly comprises a plurality of drum rotating sections 30, 32, 34, 36 and 38 arranged side by side with each other,so that the drums may lie along parallel axes to each other and transverse to the axis of the drum lying at the service station 26. As seen in the drawings, several sections 30 through 38 lie to the right of the service station 26, although in other installations, they may lie to the left.

Each of the rotating sections 30 through 38 comprise a rectangular box-like housing 40 at the top of which are mounted a pair of horizontally spaced rollers 42 and 44 forming a cradle for the drums 29. Preferably, at least one of the rollers 42 or 44 is positively driven through suitable chain or gear transmissionmeans by the motor or other drive mechanism. The non-driven roller is allowed to freely rotate. The drum 29 is formed of an elongated central body of polygonal cross- "sections provided at each end with an enlarged disk shaped end plate 46 and 48 both of which may have their centers lying along the axis of the drum and may have the same radius. In any event, the disks 46 and 48 serve as wheels, which are adapted to sit on the cradle rollers 42 and 44 and be rotated by them, thus revolving the body of the drum. Extending from the center of each of the disks 46 and 48 is a shaft pin 50 which is adapted to be borne by a suitable journal mounted in a carrier frame 52. Preferably, each drum 29 is provided with its own carrying frame 52 which form a uniform assembly. Then the drum may be carried by the frame 52 as it is transported by the conveyor 24 and deposited by the feed tower 22 at the service station.

Accordingly, it is necessary to provide means at the top of the housing 40 to receive the frame and allow the drum disks 46 and 48 to engage the rollers and at the same time free the shafts 50 from the frame 52 so that free rotation can be effected. Posts 68 and 69 are mounted to extend above the top of the housing 40 and are provided with slotted channels which receive the end portions of the frame 52. The frame 52 is provided with a vertical rib which fits into the slots of posts 68 and 69. The posts are set away from the opening in the top of the housing and thus rest on the housing allowing the drum to fall freely on to rollers 42 and 44 freeing the pins 50 from the journal bearing in the frame 52.

To transport the drums 59 back and forth between the service station 26 and the tumbling sections 30 and 38, the conveyor 24 comprises a pair of horizontal rails 70 and 72 on which a trolley motor 74 rides. Hanging from the trolley are a pair of vertical standards 76 and 78, which form an elevator, generally given numeral 80. The elevator comprises a carriage 82 which is vertically movable by a winch and chain 84. The carriage has hooks which engage beneath corresponding hooks on the upper edge of the frame 52. In this manner each drum may be individually lifted and transported.

Suitable electrical controls can be provided for effecting such movement automatically or in timed sequence.

According to the present invention, each drum may be opened and/or closed into sealed condition at the service station in automatic manner. As seen in FIG. 3, the body of the drum 29 is provided with a lid generally depicted by the numeral 180, pivotally connected by a pair of hinges 182 at each of its axial ends. Located adjacent each end of the lid is a latch means generally depicted by the'numeral 184. As seen in detail in FIG. 1,

each latch means comprises a bracket 186 which is secured to the lip or edge of the opening of the drum adjacent the end disk 46 or 48. Extending perpendicularly to the bracket 186 is a plate 188 on which a V-shaped notched locking member 190 is pivoted and loaded about a spring 192 secured about a pivot pin. The pivotal locking member 190, is biased by the action of a spring 194 secured about a pivot axle on which an engaging latching lever 196 is mounted. The latching lever 196 has a cam edge 198 which abuts the edge of the locking member 190 both of which being so contoured that the locking member may be swung by the lever into a position wherein its straight edge abuts against the bracket 186. The cam edge of the locking member has a step 200 (FIG. 5) which holds the locking member in this position, which may be referred to as the closing position.

Mounted on the lid adjacent each edge and adapted to seat within the V-shaped notch of the locking member is a transeversely extending bolt 202 which enters into the notch of member 190 when the lid is swung downwardly into closed position, as seen in FIG. 5. The open or converse position is seen in FIG. 6.

The automatic opening and closing of the lid is accomplished in the housing 26 of serve station 20 by mounting the drum 29 and its frame 52 in a device generally depicted by the numeral 204 in FIG. 2. The device 204 comprises a pair of vertical post members 206 which are mounted on spaced supports which provide a shoulder on which the frames 52 rest allowing the drum 29 to drop a pair of inwardly directed supports holding the drum by its end disks and allowing it to be rotated as needed. Operating means are mounted in each of the posts 206 to effect the unlatching or latching of the locking member 190. These operating means are seen more clearly in FIGS. 10 and II and comprise an angular lever 208 which is pivoted at one end 210 about an axis which lies perpendicular to the axis of the drum, to a rocking lever 212, which is itself pivotally mounted to rotate about a shaft 214 which lies in an axis parallel to the drum. The rocker lever 212 is spaced from a vertical block 216 (FIG. 9) and is swingable by a piston cylinder actuator 218 mounted on the block 216. The rocker lever 212 is normally drawn inwardly against a fixed stop 220 by a spring 222. The operating lever 208 is pivoted about the axis 210 by a piston cylinder actuator 224 fixed at one end to shaft 214. The lever 208 comprises a crank rod having a connecting arm 226 secured to the end of the piston of actuator 224, a central arm portion 228 and a terminal arm 230 which has a free end extending over the radial disk ends 46 or 48 of the drum to work against the latching lever 196. In FIG. 10 the lever 208 is shown in its unengaged or nonworking position. In FIG. 11, the lever 208 is shown in its engaged or working position vis-a-vis latching lever 196. In order to secure the lid 180 in its closed position, the operating lever 208 is actuated and after the drum has be rotated in the position seen in FIG. 9, the actuator 224 is operated so that the lever 208 swings it about the axis 210 and the free arm 230 is moved into the plane of the latching lever 196 and to the right of it, as seen in FIG. 9. Thereafter. the actua tor 218 is operated to swing the rocking lever 212 in the direction of the arrow in FIG. 9. This causes the latching lever 196 to be pushed by the lever 208 and to move into the closed position seen in FIG. 5.

As seen in FIGS. 3, 4 and 7 9, the drum can take different positions in the service station 26, corresponding to the need to empty, fill, close or open the drum. These positions may be controlled automatically by electrical control circuiting which includes three open contact working switch means 232, 234 and 236 which are mounted on the interior face of one of the outside walls of the housing 26. These switch means are adapted to be engaged by connecting contacts 232', 234 and 236' corresponding thereto and mounting on the exterior face of the end disk 46. The contacts 232, 234' and 236' are radially spaced from the center of the drum and offset from a diametrical axis to provide the proper timing and sequence and act to close the electrical switches and circuits for moving or operating on the drum. The contacts are arranged so that the desired operation of the drum can be effected as required.

instead of the open contact switch means other suitable switches, such as micro-switches, which are actuated by suitable cam means.

Each latching device 184 is opened by engagement with a striking member 238 which is mounted in the wall of the housing 26 and which extends upwardly along the face of the end disk 46 to move into engagement with the latching lever 196 when the drum is moved in the direction of the arrow in FIGS. 3 and 4. The striker lever 238 is mounted below the supporting pins of the drum so that it strikes the latching lever 196 only when the closing lid 180 is at the bottom and only when the lid will fall open by gravity once the latch 184 is opened. By following FIGS. 3 to 6 the action of the striker lever 238 on the latching lever 196 will be observed. Preferably, one of the levers 238 is made to pivot about an axis in a small are lying in the path of and is adapted to engage the contact associated with switch 232. As a result this lever closes the circuit in which switch 232 is arranged and is then capable of provided a further working operation on the drums, at the service station.

The switch 234 serves to stop the drum driving mechanism as soon as the drum takes the position seen in FIG. 8. In this position the closure lid 180 falls by itself into its locked position. The other switch 236 serves to stop the drum drive mechanism when the drum is in the position of FIG. 7 wherein the closure lid is in its open position. In addition, this latter switch serves to activate the feed mechanism by which material, media, etc. may be fed to the open drum.

The operation of the device is as follows:

In FIG. 1 a drum 29 is placed at the service station after having been first positioned at the work station 38 where the material had been treated. The drum 29 was transported by the conveyor 24 to the open top table 26. After placing the drum on the table 26, it is rotated by the motor means acting on one of the support pins until such time as the latching lever 196 is engaged by the striker lever 238 which then opens the latch 184. Simultaneously, the contact 232' engages the switch 232 closing an operating circuit which stops the rotation of the drum. As soon as this occurs, the notch latch 190 releases the pin 202 and the lid 180 falls by its own weight allowing the contents of the drum to fall on the sieve 28. After the drum is emptied the strike lever 238 returns to its original position, allowing the circuit to close again and the drum to be driven once more until it reaches the position shown in FIG. 7. Here the closure lid is open and the latch 184 is also open because, as the drum rotatescounterclockwise as seen in the drawings, the weight of the lid maintains itself open. In this connection it is desired that the drum should not be set in any predetermined rotary position in the service station. It can, however, happen that the drum is placed in such a position that the latching lever 196 seen in the transverse direction of the drum lodges even insignifigantly under the striker lever 238, while the contact 236 is in the area of the switch 232 and therefore actuates this switch. Under this condition the pivotal striker lever 238 is not swung and therefore does not open the latch and can not close the circuit of the switch oriented with it. As a result, it is possible that the further rotation of the drum over the remaining contacts 234 or 236 operating its switches 234 and 236 can not be accomplished and that further work, as for example to open the lid, would not progress. It is therefore preferable that the feed means in the feed tower 22 be controlled so that they will not function when a closed drum is found at the filling position in the service station. In addition, the action of the operation device 204 to lock the latching mechanism should also be prevented. So long as when the drum is set into the housing 26 and the latching lever 196 does not engage the striker lever 238, the drum is rotated in the direction of the arrow, until the latching lever 196 and the striker lever come together and the latch 184 opens (FIG. 4). After the drum is emptied, the drum continues to rotate until it reaches the filling position shown in FIG. 7. At this point the drum is filled with new material and media and continued in its rotation. As the drum rotates counterclockwise the center of mass or weight of the lid shifts and the lid falls of its own weight. In this position the switch 234 is activated by the contact 234 whereby the operating mechanism for locking the latch is placed in action. Thereafter with the operation of the actuators 224, the closing lever 208 swings from the position of FIG. 10 downwardly over the end disk 46 into the position seen in FIG. 11. Thereafter by operation of the actuator 218 on the rocker lever 212, the lever 208 is caused to swing about the axis 214 as seen by the FIG. 9 arrow to close the latching lever 196 on the notch 200 and thereby lock the lid closed. The movement of the free end 230 of the lever 208 is seen in FIG. 5. Thereafter, ther closing lever 208 is returned, by the spring 220 and the actuator 224 to its original position (FIG. 10), allowing the drum to rotate further or be removed from the service station. The drum is thereafter returned to its work position 38 and the cycle repeated with another one of the drums.

What is claimed:

1. Apparatus for the surface treatment of small objects comprising a tumbling drum, the body of which is provided with a hinged lid, a pair of disks, one at each end, for supporting said drum supported on rotatable rollers disposed in a housing, said lid having closing means loacted at each end thereof adjacent said disks and first means located on said housing for effecting the locking of said closing means and second means located on said housing spaced from said first means for opening said closing means.

2. The apparatus according to claim 1 wherein in said housing is situated a service station having a means for conveying drums to andfrom it and for delivering and removing material to be tumbled and treatment media, said service station being aligned with a plurality of means for supporting and rotating drums, whereby said service station may be employed to open and close successive number of drums.

3. Apparatus according to claim 2 wherein said first means is located above the drum and said second means below said drum, and includes control means, the activation of which brings the drum into position so that the pivotally hinged lid is at the underside of the drum body to be opened by said second means and to be rotated upwardly to be closed by said first means.

4. Apparatus according to claim 1 wherein the closing means includes a pivotally arranged closing lever located on the drum body and which in closing position laterally grips a pin located on said drum body and locking levers located on said drum body adapted to cooperate with the stop means and closing means and which means in their locking position hold the closing means in their closed position.

5. Apparatus according to claim 4 wherein at least one stop means which cooperates with the closing means and locking levers is adapted to be pivoted from a ready position to a switching position and actuates the control means.

6. Apparatus according to claim 4 wherein the activating means for closing means has an angular position in its actuating position and grips the adjacent disk on the drums and is pivotable axially and vertically to a position parallel to the drum axis to activate the locking lever.

7. Apparatus according to claim 1 wherein means are located in the front face of the wheel supporting the drum for automatically actuating the control means. 

1. Apparatus for the surface treatment of small objects comprising a tumbling drum, the body of which is provided with a hinged lid, a pair of disks, one at each end, for supporting said drum supported on rotatable rollers disposed in a housing, said lid having closing means loacted at each end thereof adjacent said disks and first means located on said housing for effecting the locking of said closing means and second means located on said housing spaced from said first means for opening said closing means.
 2. The apparatus according to claim 1 wherein in said housing is situated a service station having a means for conveying drums to and from it and for delivering and removing material to be tumbled and treatment media, said service station being aligned with a plurality of means for supporting and rotating drums, whereby said service station may be employed to open and close successive number of drums.
 3. Apparatus according to claim 2 wherein said first means is located above the drum and said second means below said drum, and includes control means, the activation of which brings the drum into position so that the pivotally hinged lid is at the underside of the drum body to be opened by said second means and to be rotated upwardly to be closed by said first means.
 4. Apparatus according to claim 1 wherein the closing means includes a pivotally arranged closing lever located on the drum body and which in closing position laterally grips a pin located on said drum body and locking levers located on said drum body adapted to cooperate with the stop means and closing means and which means in their locking position hold the closing means in their closed position.
 5. Apparatus according to claim 4 wherein at least one stop means which cooperates with the closing means and locking levers is adapted to be pivoted from a ready position to a switching position and actuates the control means.
 6. Apparatus according to claim 4 wherein the activating means for closing means has an angular position in its actuating position and grips the adjacent disk on the drums and is pivotable axially and vertically to a position parallel to the drum axis to activate the locking lever.
 7. Apparatus according to claim 1 wherein means are located in the front face of the wheel supporting the drum for automatically actuating the control means. 